Development Characteristics of Chinese Fir Microspores and its Application in Cross Breeding

Using the mother plant of Sichuan Cunninghamia lanceolata seed orchard as the test material, the corresponding relationship between the external morphological development of spring male cones, microstrobilus and the development of microspores were observed. The results showed that the development of microsporophyll on the same microstrobilus was basically synchronized. The color and length of microsporophyll were closely related to the development of microspores. When the whole microstrobilus was blue and up to 5 mm long, the internal microspores were basically in the tetrad stage. When the scales among the microsporophylls lost water and turned yellow and the wall of the microsporangia turned light yellow, the internal microspores were basically at the stage of mononuclear. After collecting the male cones with the microstrobiluses in this state and placing them in a dry greenhouse for 12—24 hours, a large number of mature and vigorous pollen could be harvested.